USB type A connector, type B connector, and Hub名詞整理

Type A connector

(1) Found on host controllers and hubs, the A-style connector is a flat, rectangular interface.
(2) You can use it is to plug devices into the CPU or USB hub.
(3) It is as the USB downstream port.
(4)Use it to connect USB devices or another USB hub.
(5) The is picture of the connector:
http://www.allproducts.com/communication/kinsun/14usb-b-l.jpg

Type B connector

(1)It is designed for use on USB peripheral devices. The B-style interface is squarish in shape, and has slightly beveled corners on the top ends of the connector.
(2)It attaches directly to the device (such as a printer or digital camera).
(3)It is as the USB upstream port.
(4)Use it to connect USB devices to your computer or USB hub.
(5) The is picture of the connector:
http://www.allproducts.com/ee/fuyao/Product-200567105039-l.jpg


Downstream is data sent from your computer to the device.

Upsream is from the device to your computer.

USB Hub

This is either built into a device or is a separate unit, which carries a number of downstream USB ports available for peripherals. A hub can also be bus-powered (voltage is drawn from the PC’s bus) or self-powered (voltage is drawn from the mains). In each case an upstream port is linked to the PC.

reference:

http://www.cablestogo.com/resources/usb.asp

http://www.webopedia.com/DidYouKnow/Computer_Science/2005/usb.asp

http://74.125.153.132/search?q=cache:L2-P-DrgiFwJ:support.dell.com/support/edocs/systems/3007wfp/en/about.htm+downstream+usb&cd=3&hl=zh-TW&ct=clnk&gl=tw

http://74.125.153.132/search?q=cache:nfXlfIvxmlIJ:askville.amazon.com/Usb-dummies-explain-USB-downstream-upstream-answers-web/AnswerViewer.do%3FrequestId%3D6690405+downstream+usb&cd=1&hl=zh-TW&ct=clnk&gl=tw